Cholangiocarcinoma (CCA), a rare yet notably aggressive cancer, has experienced a surge in incidence in recent years. Presently, surgical resection remains the most effective curative strategy for CCA. Nevertheless, a majority of patients with CCA are ineligible for surgical removal at the time of diagnosis. For advanced stages of CCA, the combination of gemcitabine and cisplatin is established as the standard chemotherapy regimen. Despite this, treatment efficacy is often hindered by the development of resistance. In recent times, immune checkpoint inhibitors, particularly those that block programmed death 1 and its ligand (PD1/PD-L1), have emerged as promising strategies against a variety of cancers and are being increasingly integrated into the therapeutic landscape of CCA. A growing body of research supports that the use of PD1/PD-L1 monoclonal antibodies in conjunction with chemotherapy may significantly improve patient outcomes. This article seeks to meticulously review the latest studies on PD1/PD-L1 involvement in CCA, delving into their expression profiles, prognostic significance, contribution to oncogenic processes, and their potential clinical utility.